The design of shallow geothermal systems needs an integration between engineering geology, thermodynamics and hydraulics. Perfect design, but don't integrating the different parts, can lead to unsatisfactory results in terms of global energy efficiency. This book wants to cover this gap, illustrating last advances in research done by the geothermal research group of Department of Civil, Environmental and Materials Engineering at University of Bologna, focused on the probabilistic characterization of underground as a tool for the integrated and correct design of shallow geothermal systems for air conditioning of buildings and other thermal purposes.